Cushioning device for railroad cars



May 2, 1939 o. c. DURYEA CUSHIONING DEVICE FOR RAILROAD CARS Filed June 3, 1957 2 Sheets-Sheet 1 y 2, 1939- o. c. DURYEA 2,156,779

CUSHIONING DEVICE FOR RAILROAD CARS Filed June 3, 1937 2 Sheets-Sheet 2 Patented May 2, 1939 UNITED STATES PATENT OFFICE 2,156,779 cosmo gnic DEVICE Foe. RAILROAD cans cum 0. Duryea, Waterbury. Conn. Application June 3, 1937, Serial No. 146,187

13 Claims.

This invention relates to improvements in I cushioning devices for railroad cars and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

One of the objects of the present invention is to provide a cushioning device especially adapted for embodiment in the draft gear of a railroad car for yieldingly resisting and absorbing the imposition of a load and upon release of said load permits of a quick return of the parts to their normal position.

Another object of the invention is to provide a cushioning device for this purpose which when placed upon load, operates through a friction mechanism and a' spring and which when released from said load, operates through the spring alone to return the load receiving members to normal position.

A further object of the invention is to provide a device of this kind wherein the parts are so correlated as to be assembled together as a complete unit for association with other parts to constitute a draft gear structure.

The above-mentioned objects of the invention as well as others, together with the advantages thereof will more fully appear as the specification proceeds:

In the drawings:

Fig. 1 is a longitudinal sectionalfiiew through a cushioning device embodying thepreferred form of the invention in association with the conven-- tional follower and stop lug of a draft gear, with the parts in their normal position as when not under load.

Fig. 2 is a view in elevation of one end of the device.

Fig. 3 is a transverse sectional view throughthe cushioning device as taken on the line 3-3 of Fig. 1.

Fig. 4 is a view in end elevation of a certa friction shoe embodied in the device.

Fig. 5 is'a longitudinal sectional view through the shoe appearing in Fig. 4.

Fig. 6 is a view in elevation of the shoe appearing in Fig. 4 as viewed from the opposite end thereof.

Fig. 7 is a view in end elevation of a certain cage-like non-compressible member embodied in the improved device.

Fig. 8 is a view in end elevation of a certain friction member embodied in the device and which will be more fully referred to later.

Fig. 9 is a fragmentary longitudinal sectional view illustrating a modified form of spring for establishing and maintaining the initial pressure in the friction mechanism of the device.

The improved device is herein illustrated and will be herein described. as embodied in a draft gear for railroad cars. This is to be considered 5 only in the illustrative sense so that I do not wish to be limited thereto because, as will be apparent, the principle of the invention may also be employed in devices for other purposes in railroad cars, where the peculiar characteristics of the invention make it of advantage to do so.

Referring now in detail to that embodiment of the invention illustrated in the drawings, l0 indicates a cylindrical casing-like body open at one end and closed at the other end by the end wall H, the central portion of which is formed as an inwardly extending hollow boss l2. The open end of the casing which is of a diameter smaller than the closed end, is provided with a plurality of arcuately spaced, inwardly tapering friction surfaces l3. These surfaces which are spaced apart by portions [4 concentric with the axis of the casing, are parts of true cylindrical surfaces, the axes of which are disposed in planes converging at the axis of the casing. 25

7 Associated with each surface 13 is a friction shoe [5 of substantially an arcuate cross section. Each shoe is formed with an external surface [6 matching the associated surface l3 of the casing and each shoe is further formed with internal, oppositely angled, inner and outer end friction surfaces I1 and i8, respectively. Said lastmentioned friction surfaces are parts of true cylindrical surfaces instead of parts of a cone and the inner end surface l8 has an area less than that of the outer end surface l1. As illustrative of the fact that the surfaces l1 and I8 are parts of a cylinder, Figs. 4 and 6 show that the curved lines defining the ends of said surfaces are of the same diameter but made on diiferent centers.

2| indicates, as a whole, a pressure receiving member of substantially a bowl-shaped formation. This member includes a cylindrical body portion 2| having an outer end radial flange]! and an inner end wall 23. The inner end external portion of this member is formed with a plurality of angled surfaces 24 which are complemental to and have engagement with the surfaces ll of the shoes l5.

An axially arranged rod 25 extends through the end wall 23 of the member II and through the end wall of the hollow boss I! of the casing Ill. The ends of said rods are threaded to receive nuts 26-4, respectively, which hold the casing ll and the member 23 operatively together in their normal position, away from each other.

21 indicates a wedge member, through which the rod also extends. This wedge member is provided with a plurality of angled surfaces 23 that are complemental to andare normally engaged with the inner end surfaces ll of the shoes I. The surfaces 23 of said member 21 are arcuately spaced apart by longitudinal recesses 23, the purpose of which will soon appear. An expansion spring 33 of helical formation surrounds that part of the rod 25 between the inner end of the wedge member 21 and a collar 3| spaced therefrom, the collar abutting against a shoulder 32 of said rod.

In the assembly of the device, the nut 23 is screwed down tight to bring the various convolutions of the spring 33 into engagement to make the spring solid, after which said nut is backed off a few turns; this will open up the convolutions of the spring to an amount which provides for the necessary relative movement between the elements of the friction mechanism. Thus the spring 33 is employed to establish an initial pressure between the elements of the friction mechanism and maintain them in initial pressure condition. If desired, the ends of the rod beyond the nut 23 may be upset to prevent unscrewing of the nut.

A main resistance spring 33 is so disposed in the casing as to surround the spring 33 and the hollow boss 12 of the casing, one end of said spring abutting against the end wall ll of the casing. A non-compressible cage-like member 34 is disposed between the other end of the main resistance spring and the pressure receiving member 23 as a whole. As shown herein, said cage-like member includes an inner end ring of relatively large diameter and an outerend ring 36 of smaller diameter. The ring 35 engages the last-mentioned end of the spring 33 while the ring 33 abuts the end wall 23 of the member 20, the two rings being solidly or rigidly connected together by arms 31. These arms 31 are dis-,- posed in the recesses 23 of the wedge member 21 so that the cage-like member may be said to substantially encompass the said wedge member 21.

It is apparent that the cage-like member substantially forms a rigid extension for the spring 33 whereby the said spring offers a yielding resistance to the inward movement of the member 23 under a load or pressure imposed thereon. When said load or pressure is released, said spring operates directly through said cage to return the member 2I| to its normal position.

The various parts are assembled from the open end of the casing ll: after assembly, the nut 26 is drawn up tight on the rid 25 so that the spring 33 goes solid. Thereafter said nut 26 is backed off its end of the rod to give the necessary tolerance clearance between the several convolutions of the spring 33.

When the device as a whole is incorporated in a draft gear for a railroad car, the casing is engaged against the stop lugs 33 and the flange 22 is engaged against the follower 33 of the assoelated car.

Assume now that a load or pressure is transmitted from the follower 33so as to move the member 22 inwardly of the casing l0. By reason of the engagement of the surfaces 24 of the member 23, with the surface I! of the shoes IS, a frictional resistance is set up which tends to move the shoes inwardly of the surfaces l3 in the associated end of the casing. This inward movement of the shoes is resisted by the action of the surfaces 28 of the member 21 on the surfaces 18 of the shoes l5, this resistance being increased by the resisting action against compression of the spring 33.

As the cage 34 forms a non-compressible connection between the member 23 and the main spring 33, the resistance of this spring is added to the resistance of the friction mechanism before described, to yieldingly absorb the shock of the load thus imparted to the follower 39. Upon release of the load, the spring 33 immediately reexpands. As the cage-like member 34 provides a rigid connection between said spring and the member 23, the spring 33 operates directly through said member 34 to return the member 20 to its normal position. Thus, it is apparent that upon load or pressure release, the spring 33 does not act through the friction mechanism to re turn the member 20 to its original position.

Should the load be imposed upon the cushioning .device from that end associated with the casing end wall II, the operation is substantially the same.

It is apparent that the spring 33 operates to provide a positive release between the parts of the device without functioning through the fric-' tion mechanism. Thus, a positive separation of the parts is assured in the release movement of the device so that it is impossible for the device to remain solid upon release of the load. Therefore, it is in condition and ready to again operate efliciently for its intended purpose after each operation thereof.

In Fig. 9, I have illustrated a modified form of the invention wherein a different type of spring is employed for establishing and maintaining initial pressure for the elements of the friction mechanism. In said figure the same parts involved bear the same reference numerals as before. However, instead of employing the helical spring 30 to surround the rod 25 between the cage 34 and the collar 3|, I employ a plurality of dished apertured discs or washers 3 la, with adjacent discs or washers arranged in opposite relation. 'I'hus certain of the discs are engaged near their midportion about the aperture therein and others are engaged at their peripheral margins. In establishing the initial pressure of such a spring, the nut 26 is operated as before to draw said discs or washers substantially solid, after; which said nut is backedoif a few turns to provide the desired initial pressure as before.

While in describing the invention, I have referred in detail to the form, arrangement and construction of the various parts involved, the same is to be considered only in the illustrative sense, so that I do not wish to be limited thereto, except as may be specifically set forth in the appended claims.

I claim as my invention:

1. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end, means providing a pressure receiving member associated with the open end of the casing-like member and relatively movable in an axial direction toward and away from the other end of said casing-like member, means providing a friction mechanism between said pressure receiving member and said open end of the casing-like member, means directly engaged with both said casing member and said pressure receiving member for limiting the relative movement of said members away from each other to define the relative normal position thereof, a spring arranged in said casing-like member and engaged at one end against the other end of the casing, a pressure transmitting member between said pressure receiving member and said spring and through which said spring cooperates with said friction mechanism in offering resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring upon release of load operating directly through said pressure transmitting member upon the moved member to return the same to its normal position.

I 2. In a cushioning device for railroad cars, the

. other to define the relative normal position thereof, a pressure transmitting member engaged at one end with said pressure receiving member, a spring in said casing-like member and arranged to exert a force between a fixed part of said casing-like member and a part of said pressure receiving member through said pressure transmit ting member, said spring cooperating withsaid friction mechanism in oifering resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

3. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end, means providing a pressure receiving member associated with the open end of the casing-like member and relatively movable in an axial direction toward and away from the other end of said casing-like member, means providing a friction mechanism between said pressure receiving member and said open end of the casing-like member, a spring in said casing-like member and engaged at one end against a fixed part thereof, a non-compressible member passing through a part of said friction mechanismand arranged between the other end of said spring and said pressure receiving member, means for holding the before mentioned parts of the device in assembled relation and for defining the relative normal position between said casing-like member and said pressure receiving member, said spring cooperating with said friction mechanism in offering resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring upon release of load operating directly upon the moved member to return the same tolits normal position.

'4. In a cushioning device for railroad cars, the combination of means providing a casinglike member open at one end and there formed with internal friction surfaces, means providing friction shoes with said surfaces, means providing a pressure receiving member associated with the open end of the casing-like member and relatively movable toward and away from the other end of said casing-like member, said last-mentioned member being operatively engaged with said shoes, a spring arranged in said casing-like member, a pressure transmitting member passing through a part of said friction mechanism and engaged with said spring and said pressure receiving member and through which said spring may cooperate with said shoes in offering a resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, means for holding the before mentioned parts of the device in assembled relation and for defining the relative normal position between said casing-like member and said pressure receiving member, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

5. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end and there formed with internal friction surfaces, means providing friction shoes engaged with said surfaces, means providing a pressure receiving member associated with the open end of the casing-like member and relatively movable toward and away from the other end of said casing-like member, said lastmentioned member being operatively engaged with said shoes, a spring in said casing-like mem-- her and having one of its ends engaged with a fixed part of said casing-like member, non-compressible means passing through a part of said friction mechanism and engaged with the other end of saidspring and said pressure receiving member, means for holding the before mentioned parts of the device in assembled relation and for defining the relative normal position between said casing-like member and said pressure receiving member, said spring cooperating with said shoes in offering a resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

6. In a cushioning device for railroad cars, the combination, of means providing a casing-like member open at one end and there formed with internal friction surfaces, means providing friction shoes externally engaged with said surface and having oppositely tapered sets of internal friction surfaces, a pressure receiving member associated with the open end of said casing-like member and relatively movable toward and away from the other end of said casing-like members, said pressure receiving members being engaged with one set of internal friction surfaces of said shoes, spring pressed means engaged with the other set of internal surfaces of said shoes, a spring arranged in said casing-like member to cooperate with saidshoes and with said spring pressed means in offering a resistance to the relative movement of one of said members from its normal position to a second position under internal friction surfaces, means providing friction shoes externally engaged with said surface and having oppositely tapered sets of internal friction surfaces, a pressure receiving member associated with the open end of said casing-like member and relatively movable toward and away from the other end of said casing-like member, said pressure receiving member being engaged with one set of internal friction surfaces of said shoes, spring pressed means engaged with the other set of internal surfaces of said shoes, a spring in said casing and arranged to exert a force between a fixed part of said casing and a part of said pressure receiving member, said spring cooperating with said shoes and with said spring pressed means in offering a resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring upon release of load operating directly upon the moved member to return the same to its normal position.

8. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end and there formed with internal friction surfaces, means providing friction shoes externally engaged with said surfaces and having oppositely tapered sets of internal friction surfaces, a pressure receiving member associated with the open end of said casing-like member and relatively movable toward and away from the other end of said casing-like member, said pressure receiving member being engaged with one-set of internal friction surfaces of said shoes, spring pressed means engaged with the other set of internal friction surfaces of said shoes, a spring in said casing-like member and having one of its ends engaged'with a fixed part of said casing-like member, non-compressible means between the other end of said spring and said pressure receiving member and which noncompressible means substantially encloses said spring pressed means, said spring and non-compressible means cooperating with said shoes and with said spring pressed means in offering a resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring and said noncompressible means upon release of load operating directly upon said moved member to return the same to its normal position.

9. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end and there formed with internal friction surfaces, means providing friction shoes externally engaged with said surfaces and having oppositely tapered sets of internal friction surfaces, a'pressure receiving member associated with the open end of said casing-like member and relatively movable toward and away from the other end of said casing-like member, said pressure receiving member having surfaces engaged with one set of internal friction surfaces of said shoes, spring pressed means engaged with the other set of internal surfaces of said shoes, a spring in said casing-like member and having one of its ends engaged with a fixed part of said casing-like member, means providing a cage comprising axially spaced rings and connecting arms enclosing said spring pressed means and arranged with its rings engaged against the other end of said spring and against said pressure receiving member respectively, said spring and cage cooperating with said shoes and with said spring pressed means in opposing resistance to the relative movementof one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring and said cage upon release of load, operating directly upon the moved member to return the same to its normal position.

10. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end and there provided with internal friction surfaces, means providing friction shoes externally engaged with said surfaces and having oppositely tapered sets of internal friction surfaces, a pressure receiving member associated with the open end of said casing-like member and relatively movable toward and away from the other end of said casing-like member, said pressure receiving member having surfaces engaged with one set of internal friction surfaces of said shoes, means for limiting the relative movement of said casing-like member and said pressure receiving members away from each other to define the relative normal positions thereof, means operatively engaged with the other set of internal friction surfaces of said shoes, spring means between said movement limiting means and said last-mentioned means for urging the latter into engagement with its associated surfaces of said shoes, and a spring arranged in said casing-like member to cooperate with said shoes and said means engaged with the other set of surfaces of said shoes in offering a resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring upon release of pressure operating directly upon the moved member to return the same to its normal position.

11. In a cushioning device for railroad cars, the combination of means providing a casing-like member open at one end and there provided with internal friction surfaces, means providing fric- -tion shoes externally engaged with said surfaces said pressure receiving member being engaged with one set of internal friction surfaces of said shoes, means for limiting the relative movement of said casing-like member and said pressure receiving members away from each other to define the relative normal positions thereof, means operatively engaged with the other set of internal friction surfaces of said shoes, spring means between said movement limiting means and said last mentioned means for urging the latter ino engagement with its associated surfaces of said shoes, a spring in said casing-like member and having one of is ends engaged with a fixed part of said casing-like member, non-compressible means between the other end of said spring and said pressure receiving member and which noncompressible means substantially encloses said means engaged with the' other set of friction surfaces of said shoes, said spring and non-compressible means operating in conjunction with said shoes and with said means engaged with the said other set of surfaces on said shoes in offering a resistance to the relative movement of one of said members from its normal position to a second position under the action of a load imposed upon one of said members, said spring and noncompressible means upon release of load operating directly upon the moved member to return the same to its normal position.

12. In a cushioning device for railroad cars,

the combination of a casing member open at one end and there formed with internal friction surfaces and closed at its other end, shoes having external friction surfaces engaged with said first-mentioned surfaces and having sets of oppositely tapered internal friction surfaces, a pressure receiving member associated with the open end of said casing member and relatively movable toward and away from the closed end of the casing member, said pressure receiving member being engaged with one set of internal friction surfaces of said shoes, means arranged axially of said casing member and said pressure receiving member for limiting the relative movement of said members away from each other to define the relative normal position thereof, a third member engaged with the other set of said internal friction surfaces of said shoes and through which said means axially of the casing member also extends, a spring between said third member and a fixed part of said means axially of the casing member for urging said third member into engagement with its associated set of internal friction surfaces and said shoes, a second spring arranged in said casing and engaged at one end with the closed-end of the casing member, and non-compressible means between the other end of said second spring and said pressure receiving member and substantially enclosing said third member.

13. In a cushioning device for railroad cars,

.ward and away from the closed end of the easing member, said pressure member being engaged with one set of internal friction surfaces of said shoes, a rod arranged axially of said casing member and said pressure receiving member,

for limiting the relative movement of said menibers away from each other to define the relative normal position thereof, a third member engaged with the other set of said internal friction surfaces of said shoes and through which said rod also extends, a spring between said third member and a fixed part of said rod for urging said third member into engagement with its associated set of internal friction surfaces and said shoes, a second spring arranged in said casing and surrounding said rod and engaged at one end with the closed end of the casing member, and a cage arranged between said second spring and said pressure receiving member, said cage including end rings engaged with said other end of said second spring and said pressure receiving member respectively, and which rings are connected together by arms which are disposed in cutaway portions of said third member whereby said third member is substantially encompassed by said cage.

O'I'HO C. DURYEA. 

